After a member of a neighboring club reported this to the German Tennis Federation, Nüsslein received a lifetime ban from amateur competition, preventing him from competing at Grand Slam tournaments.

[5] In January 1930, Nüsslein reached the quarter-finals of the Bristol Cup, beating Edmund Burke before losing to Robert Ramillon.

[6] At the French Pro championships at Roland Garros, Nüsslein reached the quarter-finals before losing to Roman Najuch.

Both players showed a desire to hug the base line, with neither attempting to reach the net, save on rare occasions when a short drop shot would pull them to the forecourt.

"[8] Nüsslein finished third out of four in the concluding round robin at the World Pro Championships in Berlin in September behind Martin Plaa and Bill Tilden.

With Tilden tiring, Nusslein pushed closer into court, sometimes trapping half-volleys at the service line and moving in, often behind drop shots.

The German star gradually added pace and confidence, eventually dominating play and finally winning 1-6 6-4 7-5 6-3.

"[2] Touring South America in November, Nüsslein won the tournament at Buenos Aires over Kozeluh[9] and the Facondi brothers.

[10] Nüsslein won the Miami Pro in March beating Kozeluh in the final "timing his shots to perfection and stroking with lightning-like speed".

"Nusslein mixed soft slices to midcourt with stinging drives, to the corners and kept the Czech on the run throughout the match.

In the late thirties, Nüsslein coached the first Grand Slam winner Don Budge, the Australian Davis Cup team as well as several German players.

He won the event at Southport for the fourth year in a row beating Vines and Tilden in successive rounds.

His most prominent tennis pupils included Wilhelm Bungert, Christian Kuhnke, Dieter Ecklebe and Wolfgang Stuck.

Tennis historian Robert Geist described his playing style: "He possessed classic strokes, equal to Hall of Famers René Lacoste, Henri Cochet, and Karel Koželuh, as well as excellent volleys, magnificent drop shots and breath-taking half-volleys.